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Recommended sampling rate

Your router samples the traffic that passes through it to create NetFlow or sFlow data. The sampling rate determines how frequently your router captures a packet — for example, a rate of 1 in 100 means your router captures one out of every 100 packets.

Sampling more frequently (lower ratios like 1 in 100) produces more accurate flow data but uses more router memory and CPU. Sampling less frequently (higher ratios like 1 in 4,000) reduces resource usage and is suitable for networks with larger traffic volumes.

The following table provides general recommendations based on your traffic volume. Test different sampling rates to find the best option for your network.

Traffic VolumeRouter sampling recommendation
LowBetween 1 in 100 packets - 1 in 500 packets
MediumBetween 1 in 1,000 - 1 in 2,000 packets
HighBetween 1 in 2,000 - 1 in 4,000 packets

As a general rule, you may notice a loss in data accuracy (depending on your network volume) when your network flow sampling rate exceeds 1 in 5,000 packets.